One of the oldest scientific gardens in Britain, containing more than 13,302 plant species in its core collection.

This allegedly haunted 16th-century tower house-turned-museum exhibits thousands of spectacular objects.

Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

Even though some of the buildings date back to the Victorian era, this research institute is still involved in cutting-edge astronomy research.

This historic timepiece was a popular meeting place for romantic rendezvous in the 1960s.

A public art piece that barely gets recognized, but then that might be the point.

This modern work of art was a refreshing addition to one of the oldest theatres in the city.

Neon artworks light up this dark Edinburgh tunnel.

This stately bank building hides a spectacular star-studded ceiling.

This alley off Edinburgh's Royal Mile contains remnants of the city's seedier history.

Anonymously sculpted and donated, these sculptures made from poetry books and pages are sprinkled around the city.

Now home to a drinking establishment, this building has a macabre history.

Sprawled across the Great Hall ceiling are various constellations and images relating to the zodiac.

An old limestone mine transformed into a beautiful and unusual sculpture museum.

An ultra-modern diversity park in Denmark has turned an entire city block electric pink.

Hans Christian Andersen for the postmodern world.

Six beautiful wooden giants are hidden around Copenhagen.

A 19th-century subterranean reservoir repurposed as a contemporary art cave.

The Natural History Museum that time forgot.

World's largest cave was only discovered in 1991, and now offers tours to the public.

This Vietnamese hell cave lets visitors take a walk through a devilish underworld full of demons.

An old department store turned Nazi prison turned artist commune.

Tubing through a cave lit with glowworms is a magical underground experience.

Three wildly colorful calderas top this otherworldly volcano chain.